High COVID-19 morbidity and mortality risk among smoked drug users in Brazil

Abstract In much of the West, including Brazil, drug use has increased since social distancing began in response to the pandemic. Use of smoked and modified drugs, and their impacts on health, may contribute to aggravate the effects of the pandemic. However, studies on the relationship between use of smoked drugs and the new coronavirus are still scarce and have not received enough attention in global health recommendations. This paper aims to briefly review the relationship between use of smoked drugs and acute respiratory syndrome coronavirus 2 [SARS-CoV-2]. Recent studies also suggest that drug consumption increases the risk of contamination by SARS-CoV-2 and leads to worse prognosis, particularly consumption of drugs that affect lung function. Use of smoked drugs, especially tobacco, is strongly associated with lung diseases that are risk factors for contamination by SARS-CoV-2. It is essential to develop strategies based on specific characteristics of drug users and for mental health professionals to be included in strategic teams. It is also necessary to invest in information campaigns regarding risks and prevention of harm caused by smoked drugs as well as to design strategies that facilitate access to psychosocial treatment during the pandemic.

Severe acute respiratory syndrome coronavirus 2 [SARS-Cov-2] is a virus that can cause respiratory diseases and other inflammatory illnesses, with poor outcomes. Since the beginning of the coronavirus pandemic, thousands of people have been infected worldwide. 1,2 The mortality rate due to SARS-CoV-2 infection varies across locations (from 0.00% to 1.63%, corrected values from 0.00% to 1.54%) 3 and may change substantially depending on health care infrastructure and prevention measures. 4,5 There is an urgent need to identify risk factors for infection by SARS-CoV-2 and for progression to worse clinical outcomes. Although it is well documented that some diseases increase the risk of death from the Coronavirus disease 2019 , this relationship is not yet well understood. Recent studies have suggested that drug use significantly increases the risk of infection by SARS-CoV-2 6 and leads to worse prognosis, particularly use of drugs that affect lung functions. [7][8][9] Previous evidence has shown that cannabis and tobacco users are at higher risk of infection by influenza and of developing severe respiratory syndromes. Moreover, studies with animal models have shown that smoked drugs cause changes to the respiratory system from the nasal mucosa to the lung parenchyma. [10][11][12] It is also necessary to consider that people who use cannabis and crack cocaine may share drugs or pipes with other people, and that concomitant use of tobacco may further increase risks. [13][14][15][16][17] Considering these clinical findings, it might be the case that smoked drugs increase the risk of contamination by SARS-CoV-2.
However, studies assessing the relationship between smoked drug consumption and SARS-CoV-2 are still scarce and have not received enough attention in global health recommendations. 18 In Brazil, prevalence rates of regular use are 9.8% for tobacco 19 and 2.5% for marijuana. 20 Although these rates are lower than in many other countries, populations with low socioeconomic status have higher rates of use than the general population. 21,22 Additionally, Brazil is one of the largest crack cocaine markets 23 worldwide and 0.9% of the population use crack. 20 Recent studies have shown that crack cocaine users are subject to multiple clinical and social vulnerabilities 24 and that the prevalence of diseases associated with the severity of COVID-19 may be higher among users of tobacco, marijuana, and crack cocaine than in the general population. 6 In the context of the current pandemic, in which Nevertheless, research addressing the consequences of drug use for progression of the pandemic is still scarce.
This paper aims to briefly review the relationship between use of smoked drugs and COVID-19.

Tobacco
Smoking is known to increase the risk for several comorbidities, including diabetes, 28 cardiovascular disease, 29 and chronic obstructive pulmonary disease (COPD), 30 all of which appear to play an important role in the pathology of COVID-19 in humans. 31 Conversely, other studies have suggested that the nicotinic acetylcholine receptor plays a key role in the pathophysiology of COVID-19 and may constitute a prevention strategy. 42 However, the data supporting the hypothesis that nicotine helps to prevent COVID-19 are still scarce, and the results remain controversial. 43,44

Electronic cigarettes or vaporizers, and hookahs
Tobacco is available in different forms for consumption, with electronic cigarettes -or vaporizers -and hookahs becoming popular among young people. 45 Electronic cigarettes, or e-cigarettes, deliver nicotine mixed with several types of flavors, making "vaping" (inhaling vapor created by e-cigarettes) a more palatable experience than smoking. Electronic cigarettes and hookahs are currently a social experience for young people because they may be shared in groups, which increases the risks of viral transmission. 45,46 These devices have affordable prices and convey a false impression of being less harmful than smoking. 47 In reality, they may be even more damaging than industrialized cigarettes, since a hookah session of 20 to 80 minutes is equivalent to exposure to 100 cigarettes. 48 The concentration of nicotine in these devices is unknown due to an absence of regulatory policies and they may therefore be more toxic than traditional cigarettes. It is still unclear whether cannabis use leads to the same COVID-19 outcomes observed in tobacco smokers. However, a study has reported evidence that marijuana users may be at increased risk if infected with coronavirus. 9 It is well known that cannabinoids have deleterious effects on pulmonary function and inflammation by affecting the release of respiratory pathogens, which might increase the "cytokine storm" in COVID-19. 65 Long-term cannabis consumption leads to effects similar to those observed in tobacco users or even more clinically deleterious effects. 66,67 A recent study reported the case of a patient with a history of asthma who sought care at an emergency room with symptoms resembling those of COVID-19: fever, chills, dry cough, dyspnea, myalgia, increased respiratory rate, diarrhea, and low saturation. A chest X-ray showed bilateral interstitial infiltrates. As a result of clinical suspicion, the patient was isolated and treated for SARS-CoV-2, which was later ruled out by testing.
After a positive toxicological result for marijuana, the patient acknowledged using the substance with e-cigarettes 3 times per week for the past two years.
This prompted a change in the therapeutic approach.
Despite being a case report, this study highlights the importance of differential diagnosis. 68

Crack cocaine
Another smoked drug that warrants concern is crack cocaine. Brazil is one of the main crack-consuming markets in the world and this drug is used mainly by vulnerable populations. 23

Conclusion
Use of smoked drugs, particularly tobacco, is associated with lung diseases that are risk factors for contamination by SARS-CoV-2. Additionally, in much of the West, drug use has increased since social distancing began in response to the COVID-19 pandemic; such an increase may contribute to aggravating the effects of the pandemic through the consequences of smoking and drug sharing for the health of users. It is essential to develop strategies based on specific characteristics of drug users and for mental health professionals to be part of strategic teams. It is also necessary to invest in information campaigns regarding risks and prevention of harm caused by smoked drugs, as well as to design strategies that facilitate access to psychosocial treatment during the pandemic.